Semiconductor device

1. A semiconductor device comprising: a semiconductor module comprising a semiconductor element, a resin package sealing the semiconductor element, and a heat sink located at a main surface of the resin package, the resin package comprising a pair of side surfaces each adjacent to the main surface and opposite to each other; an insulating sheet covering the heat sink; a cooling plate which is constituted of resin containing heat transfer fillers, the cooling plate having a first surface and a second surface opposite from the first surface, wherein the first surface covers the insulating sheet and is in direct contact with the main surface of the resin package around the insulating sheet, and the second surface is provided with fins; and a cooler constituted of resin and at least partly defining a coolant passage configured to flow coolant along the fins, wherein the cooler surrounds the cooling plate in a view along a normal direction of the cooling plate, and is in direct contact with each of the pair of side surfaces of the resin package, wherein a peripheral edge of the cooling plate is separated from the cooler by a gap; the gap extends from the coolant passage to the main surface of the resin package such that the coolant passage is partly defined by the main surface of the resin package; the cooler directly contacts the main surface of the resin package around the peripheral edge of the cooling plate; and the cooler comprises an outer cylinder at least partly defining the coolant passage and at least two beams provided in the outer cylinder and being in direct contact with the pair of side surfaces and the main surface of the resin package.

2. The semiconductor device according to claim 1 , wherein the heat transfer fillers have an elongated shape, and the heat transfer fillers in each of the fins are oriented with their longitudinal direction in a direction from a base toward a tip of the fin.

3. A semiconductor device comprising: a semiconductor module comprising a semiconductor element, a resin package sealing the semiconductor element, and a heat sink located at a main surface of the resin package, the resin package comprising a pair of side surfaces each adjacent to the main surface and opposite to each other; an insulating sheet covering the heat sink; a cooling plate which is constituted of resin containing heat transfer fillers, the cooling plate having a first surface and a second surface opposite from the first surface, wherein the first surface covers the insulating sheet and is in direct contact with the main surface of the resin package around the insulating sheet and the second surface is provided with fins; and a cooler constituted of resin and at least partly defining a coolant passage configured to flow coolant along the fins, wherein the cooler surrounds the cooling plate in a view along a normal direction of the cooling plate, and is in direct contact with the pair of side surfaces of the resin package, wherein the cooler comprises an outer cylinder at least partly defining the coolant passage and at least two beams provided in the outer cylinder and being in direct contact with the pair of side surfaces and the main surface of the resin package.